Naruto has some of the best side character stories in all of anime, as each character has a unique personality, which is embodied in how and why they became shinobi.
There are countless examples of such characters, with the most famous ones being Rock Lee, how he prevailed as a strong shinobi despite having no chakra, Itachi, who had to sacrifice his clan for the wellbeing of the Hidden Leaf Village, Kakashi, who trained a new team of young ones while hiding his grief from the past, and many others.
But today's discussion is the teacher of Team 10 that featured the Ino-Shiki-Cho trio, Asuma Sarutobi. He died while fighting the Akatsuki and before he passed away, he whispered some words which were revealed later in the series, of which most fans are not aware.
Naruto: Asuma Sarutobi's last message to Shikamaru before he died
Asuma Sarutobi was a jounin who belonged to the Hidden Leaf Village. He was introduced in episode 3 of Naruto as the teacher/trainer of Team 10. This team comprised the legendary trio of Ino-Shika-Cho, namely Ino Yamanaka, Shikamaru Nara, and Choji Akimichi.
Asuma was also the son of the Third Hokage, Hiruzen, and seven years before the current timeline, he was a part of the Twelve Guardian Ninja. After losing Obito and Rin during the Third Ninja War, Asuma was part of the group that convinced Hiruzen to take Kakashi out of the Anbu and make him a teacher alongside them.
Asuma was a very kind person, as he treated his students like his own children. Out of the three he was put in charge of, Shikamaru stood out as Asuma's favorite and they enjoyed playing shogi in their free time. While playing, they usually personified the shoujo pieces with village people, and Shikamaru was stuck on who the Black King of shogi was.
During the Akatsuki Suppression Mission, Asuma was overwhelmed by Hidan, an Akatsuki member, and got fatally injured. His team arrived to save him but it was too late. He delivered his parting words to Ino and Choji and whispered who the "Black King" of shogi was in the ears of Shikamaru. Later in the series, there wasn't a reveal as to what Asuma said, so what did the Black King symbolize?
A few episodes later, the Hidden Leaf Shinobi returned to exterminate the two Akatsuki members, Kakuzu and Hiden. Shikamaru was solely focused on killing Hidan to avenge his teacher, but killing him would be hard as he was immortal. So, Shikamaru used his intellect and cornered Hidan.
He blasted him into pieces and buried him underground so that even if he regenerated, he wouldn't be able to move because of the pressure of Earth in his body. After he buried Hidan, Asuma's soul appeared and passed on his will to Shikamaru.
After returning to the village, while Shikamaru was playing shogi with his father, he asked Shikamaru who the Black King was. To which Shikamaru replied:
"It is children of the Hidden Leaf who carry the village on their shoulders."
He could be referring to how the progress of a society depends on how the young ones, the future of that society, adapt to everything, meaning everything is dependent on them, thus making them kings.
Shikamaru never knew the answer to this question, but during Asuma's last moments, he told Shikamaru the meaning of the Black King, meaning these were Asuma's last words to Shikamaru. Coincidently, Asuma's child was also named Mirai Sarutobi, which in Japanese means "future."
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